Localization of Receptors for Sex Steroids and Pituitary Hormones in the Female Genital Duct throughout the Reproductive Cycle of a Viviparous Gymnophiona Amphibian, .

Reproduction in vertebrates is controlled by the hypothalamo-pituitary-gonadal axis, and both the sex steroid and pituitary hormones play a pivotal role in the regulation of the physiology of the oviduct and events occurring within the oviduct. Their hormonal actions are mediated through interaction with specific receptors. Our aim was to locate α and β estrogen receptors, progesterone receptors, gonadotropin and prolactin receptors in the tissues of the oviduct of (Amphibia, Gymnophiona), in order to study the correlation between the morphological changes of the genital tract and the ovarian cycle.

Immunohistochemical Localization of Calpains in the Amphibian Xenopus laevis.

Though histochemical techniques have been used for decades, they are still very important in basic research. They make it possible to work on fixed tissues and provide a large amount of information in a relatively short time and at a low cost. Here we describe methods for indirect immunohistochemistry and immunofluorescence on sections of tadpoles and tissues of adult amphibians belonging to the species Xenopus laevis.

Patterns of Apoptosis and Proliferation throughout the Biennial Reproductive Cycle of Viviparous Female Typhlonectes compressicauda (Amphibia, Gymnophiona).

is an aquatic gymnophionan amphibian living in South America. Its breeding cycle is linked to seasons, characterized by a regular alternation of rainy and dry seasons. During a complex biennial cycle, the female genital tract undergoes a series of alternations of increasing and decreasing, governed by equilibrium of proliferation and apoptotic phenomena.

Relationships between calpains and glutamate- or kainate-induced apoptosis in Xenopus laevis tadpoles.

Cell glutamate-damage induced by overstimulation of ionotropic receptors is initiated by modification of the intracellular Ca2+ homeostasis and the concomitant activation of Ca2+-dependent cysteine proteases, the calpain and caspase families. The resultant cleavage of target molecules mediates a critical function in the execution of the cell death. In this work, we investigated relationships between the activity of calpain and glutamate-orkainate-induced apoptosis in several organs of Xenopus laevis tadpole.